Comparative metatranscriptomic signatures of wood and paper feeding in the gut of the termite Reticulitermes flavipes (Isoptera: Rhinotermitidae)

Abstract

Termites are highly eusocial insects that thrive on recalcitrant materials like wood and soil and thus play important roles in global carbon recycling and also in damaging wooden structures. Termites, such as Reticulitermes flavipes (Rhinotermitidae), owe their success to their ability to extract nutrients from lignocellulose (a major component of wood) with the help of gut-dwelling symbionts. With the aim to gain new insights into this enzymatic process we provided R. flavipes with a complex lignocellulose (wood) or pure cellulose (paper) diet and followed the resulting differential gene expression on a custom oligonucleotide-microarray platform. We identified a set of expressed sequence tags (ESTs) with differential abundance between the two diet treatments and demonstrated the source (host/symbiont) of these genes, providing novel information on termite nutritional symbiosis. Our results reveal: (1) the majority of responsive wood- and paper-abundant ESTs are from host and symbionts, respectively; (2) distinct pathways are associated with lignocellulose and cellulose feeding in both host and symbionts; and (3) sets of diet-responsive ESTs encode putative digestive and wood-related detoxification enzymes. Thus, this study illuminates the dynamics of termite nutritional symbiosis and reveals a pool of genes as potential targets for termite control and functional studies of termite-symbiont interactions.

The Role of Host Phylogeny Varies in Shaping Microbial Diversity in the Hindguts of Lower Termites

“…Moreover, the microbial community itself can create these microenvironments (67). Biochemical coordination of the symbiont community with their host to extract nutrition also likely influences symbiont diversification (68,69). The biology of the symbionts must also complement the biology and behavior of the host.…”

Linking lignocellulosic dietary patterns with gut microbial Enterotypes of Tsaitermes ampliceps and comparison with Mironasutitermes shangchengensis

“…The diversity and complexity of the termite gut microbiota have been evaluated using molecular technology techniques based on 16S rRNA (Warnecke et al, 2007;Berlanga et al, 2011;Mathew et al, 2012). Recent studies have indicated that different dietary habits shape the structure of microbiota in the termite gut (Boucias et al, 2013;Huang et al, 2013;Raychoudhury et al, 2013). Dietary manipulation induces measurable differences among gut bacterial communities, and the recalcitrance of plant substrates may be the major cause of this variation in the diversity and richness of gut bacterial communities (Boucias et al, 2013;Huang et al, 2013;Raychoudhury et al, 2013).…”

“…Recent studies have indicated that different dietary habits shape the structure of microbiota in the termite gut (Boucias et al, 2013;Huang et al, 2013;Raychoudhury et al, 2013). Dietary manipulation induces measurable differences among gut bacterial communities, and the recalcitrance of plant substrates may be the major cause of this variation in the diversity and richness of gut bacterial communities (Boucias et al, 2013;Huang et al, 2013;Raychoudhury et al, 2013). However, influences on the abundance and diversity of the intestinal microbial of termite fed with different substrates containing various lignin and cellulose or hemicellulose remain unclear.…”

Saccharification of Agricultural Lignocellulose Feedstocks and Protein-Level Responses by a Termite Gut-Microbe Bioreactor

“…In addition to secreting host-derived digestive enzymes, this lower termite harbors a diversity of eukaryotic (protist) and prokaryotic (bacteria) symbionts in its hindgut, which is analogous to a fermentation chamber (Watanabe and Tokuda, 2010;Brune, 2014). Comparison of metatranscriptome profiles for wood and paper (cellulose)-fed termites has shed much light on putative lignocellulose degrading enzymes and detoxification enzymes potentially involved in lignin and metabolite degradation (Raychoudhury et al, 2013). In addition, detoxification and antioxidant enzymes including phenoloxidases, laccases, esterase, cytochrome P450s, catalases, superoxide dismutases, and glutathione peroxidases (GPX) were previously found upregulated in termites fed on lignin phenolics (Tartar et al, 2009;Coy et al, 2010;Sethi et al, 2013).…”